The orbital cavity is drained by paired veins called the superior and inferior ophthalmic veins. The superior ophthalmic vein arises at the inner angle of orbit and follows the course of ophthalmic artery into the cavernous sinus, a greatly dilated (widened) channel of venous blood. The inferior ophthalmic vein arises from a venous network at the forepart of orbit and divides into two branches one of which also ends in the cavernous sinus. The corresponding eye artery is called the ophthalmic artery. It supplies blood not only to the eye but also to adjacent structures of face. It arises from the internal carotid artery that courses up deep within the front of the neck.

ophthalmic vein — n either of two veins that pass from the orbit: a) one that begins at the inner angle of the orbit and passes through its superior part and through the superior orbital fissure to empty into the cavernous sinus called also superior ophthalmic… … Medical dictionary

Ophthalmic veins — The orbital cavity is drained by paired veins called the superior and inferior ophthalmic veins. The superior ophthalmic vein arises at the inner angle of the orbit and follows the course of the ophthalmic artery into the cavernous sinus, a large … Medical dictionary

Emissary veins — Vein: Emissary veins Latin vena emissaria The emissary veins are valveless veins which normally drain external veins of the skull into the dural venous sinuses. However, because they are valveless, pus can flow into the skull through them as well … Wikipedia

Diploic veins — Vein: Diploic veins Veins of the diploë as displayed by the removal of the outer table of the skull. Latin venae diploicae Gray s … Wikipedia